(a) Field
The described technology generally relates to a display device and a driving method thereof.
(b) Description of the Related Technology
An organic light emitting diode (OLED) display displays an image by using an OLED which generates light by recoupling an electron and a hole. OLED displays generally have a rapid response speed, consume low power, and have excellent emission efficiency, luminance and viewing angle, and thus have drawn attraction.
Generally, an OLED display is classified into a passive matrix OLED display (PMOLED) and an active matrix OLED display (AMOLED) according to a driving mode of the organic light emitting diode.
The passive matrix type is a driving mode in which a positive electrode and a negative electrode are formed to be perpendicular to each other and a negative electrode line and a positive electrode line are selectively driven, and the active matrix type is a driving mode in which a thin film transistor and a capacitor are integrated in each pixel to maintain voltage by capacitance. The passive matrix type has a simple structure and is cheap, but it is difficult to implement a large-sized or high-precision panel. On the contrary, the active matrix type may implement the large-sized or high-precision panel, but there are problems in that a control method thereof is technically difficult and costs are relatively high.
From the viewpoint of resolution, contrast, and operation speed, the active matrix organic light emitting diode display (AMOLED) in which light is selectively emitted for each unit pixel has become a mainstream.